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Single-board computer

A single-board computer (SBC) is a completecomputer built on a single circuit board, with microprocessor, memory,input/output and other features required of a functional computer.

Single-board computers were made asdemonstration or development systems, for educational systems, or for use asembedded computer controllers. Many types of home computer or portable computerintegrated all their functions onto a single printed circuit board.

Unlike a desktop personal computer, singleboard computers often do not rely on expansion slots for peripheral functionsor expansion. Some single-board computers are made to plug into a backplane forsystem expansion. Single board computers have been built using a wide range ofmicroprocessors. Simple designs, such as built by computer hobbyists, often usestatic RAM and low-cost 8 or 16 bit processors.

Trivial File Transfer Protocol

Trivial File Transfer Protocol (TFTP) is a simple, lockstep, File Transfer Protocol which allows a client to get from or put a file onto a remote host. One of its primary uses is in the early stages of nodes booting from a local area network. TFTP has been used for this application because it is very simple to implement.

Overview

Due to its simple design, TFTP can be easily implemented by small footprint code. It is therefore the protocol of choice for the initial stages of any network booting strategy like BOOTP, PXE, BSDP, etc., when targeting from highly resourced computers to very lower sourced Single-board computers (SBC) and System on a Chip (SoC). It is also used to transfer firmware images and configuration files to network appliances like routers, firewall, IP phones, etc. Today, TFTP is virtually unused for Internet transfers.

TFTP is a simple protocol for transferring files, implemented on top of the UDP/IP protocols using well-known port number 69. TFTP was designed to be small and easy to implement, and therefore it lacks most of the advanced features offered by more robust file transfer protocols. TFTP only reads and writes files from or to a remote server. It cannot list, delete, or rename files or directories and it has no provisions for user authentication. Today TFTP is generally only used on local area networks (LAN).